The survival or failure of a cornea allograft is determined by a variety of factors including histocompatibility antigen differences between donor and recipient, the immunologic competence of the recipient, previous immunologic exposure of the recipient to graft antigens, immunologic competence of the recipient, size of the graft and the degree of post-transplantation inflammation and vascularization at the graft site. The objectives of the research proposed in this application are to investigate the contribution of several of these factors to the rejection process and to develop and test a protocol for inhibiting corneal allograft rejection. Interlamellar cornea grafts will be exchanged between presensitized nd non-immune rats of two inbred strains which differ from each other at the major Ag-B histocompatibility locus. The importance of ghost-vessels and prior cornea inflammation in graft rejection will be determined by comparing the percent of grafts rejected by rats in whose corneas an inflammatory response was induced with the percent rejected by rats having no history of corneal inflammation. The protocol for inhibiting cornea allograft rejection involes the suppression of an idiotypically specific T-lymphocyte response to graft antigens by eliciting an anti-idiotypic response in the host. In vivo and in vitro tests for idiotypic suppression will be conducted in order to establish that the suppression is immunologically specific and is due to a suppression of specific clones of lymphocytes.